The synthesis of phosphopeptides

Phosphorylation and dephosphorylation are key events in protein expression and regulation and in signal transduction. Phosphopeptides are very useful reagents for the study of these processes, and have been used to great adva ntage in the study of phosphatase substrate specificity, SH2 domain ligand specificity and protein-protein interactions. Furthermore, the advent of ce ll-permeable peptide carriers, such as those from the antennapedia homeodom ain and the HIV TAT transcription factor has allowed the study of intracell ular events, thus underscoring the utility of these reagents. In this paper we review methods for the synthesis of phosphopeptides with the emphasis o n the preparation of phosphoamino acid building blocks. (C) 2001 John Wiley & Sons, Inc.